1. Field of the Invention
The present invention relates to a method for preparation of plasma powder, more specifically to a method for preparation of plasma powder which is substantially free of malodorous substances.
At present, plasma powder prepared from plasma of bovines, swine and other animals are used mainly as a food quality improver for ham, sausages and other foods. However, since plasma powder characteristically has a nasty odor and taste, it can be used only in such very small amounts that its addition does not affect the flavor of food. It is therefore demanded that plasma powder having no malodor and improved taste be provided.
The method for preparation of plasma powder of the present invention provides plasma powder having no malodor and improved taste which does not adversely affect the flavor of food.
2. Description of the Prior Art
Blood of a bovine, swine or other animal is collected at a slaughterhouse. The collected blood is immediately supplemented with sodium citrate to prevent its coagulation, after which it is centrifuged to separate plasma and blood cells. Since liquid plasma is not easy to handle and has drawbacks in storage and distribution due to bacterial contamination etc., it is common practice to powder the plasma by spray drying or another means.
Traditionally, powdering has been carried out by drying plasma either directly after its separation from blood or after pretreatment by ultracentrifugation. Also, investigations have been made on deodorization with activated charcoal, but this method remains undeveloped.
However, the conventional plasma powder thus obtained has a characteristic undesirable odor and taste. The bad odor and taste become stronger with the elapse of time, such that, the commercial plasma powder products all have a nasty odor and taste after a given period following preparation even if the initial odor and taste were weak. Plasma powder is used as a food quality improver, particularly for the purpose of water retention and elasticity enhancement, but the amount of its addition is limited. Accordingly, the obtained effect is often unsatisfactory, since if it were added in large amounts, the flavor of food would be affected by the nasty odor and taste described above. It is therefore needed to produce plasma powder having no malodor and improved taste which does not spoil the flavor of food.